The present technology relates to a voltage detector, an electronic device, and a control method of the voltage detector. In particular, the present technology relates to a voltage detector that detects a power supply voltage of a defined voltage or lower, an electronic device, and a control method of the voltage detector.
In recent years, developments in miniaturization and power saving of electronic devices are remarkable and each device in an electronic device is frequently demanded to perform a correct operation at low voltage. To guarantee an operation at low voltage, a voltage detector that detects whether a power supply voltage VDD is higher than a constant defined voltage is used in electronic devices. For example, a voltage detector including a reference voltage generator circuit that generates a constant reference voltage Vref and a comparator is proposed (see, for example, “S-808xxC series”, p2-p24, [online], Seiko Instruments Inc., [searched on Apr. 26, 2013], Internet <URL: http://datasheet.sii-ic. com/jp/voltage_detector/S808xxC_J.pdf>). The comparator divides the power supply voltage VDD in the ratio of the reference voltage Vref to the defined voltage and compares the divided voltage and the reference voltage Vref to detect whether the power supply voltage VDD is higher than the defined voltage.
By switching processing of the power supply and backup processing being performed by electronic devices based on the detection result, a correct operation of electronic devices at low voltage that is lower than the defined voltage is guaranteed.